<template>
  <div id="home">
    <nav-bar class="home-nav"><div slot="center">购物街</div></nav-bar>
    <tab-control
      :titles="['流行', '新款', '精选']"
      @tabClick="tabClick"
      ref="tabControl1"
      class="tab-control"
      v-show="isTabFixed"
    ></tab-control>
    <scroll
      class="content"
      ref="scroll"
      :probe-type="3"
      @scroll="contentScroll"
      :pull-up-load="true"
      @pullingUp="loadMore"
    >
      <home-swiper
        :banners="banners"
        @swiperImageLoad="swiperImageLoadhandle"
      ></home-swiper>
      <recommend-view :recommends="recommends"></recommend-view>
      <feature-view></feature-view>
      <tab-control
        :titles="['流行', '新款', '精选']"
        @tabClick="tabClick"
        ref="tabControl"
      ></tab-control>
      <goods-list :goods="showGoods"></goods-list>
    </scroll>
    <back-top @click.native="backClick" v-show="topIsShow"></back-top>
  </div>
</template>

<script>
import HomeSwiper from "./childComps/HomeSwiper";
import RecommendView from "./childComps/RecommendView";
import FeatureView from "./childComps/FeatureView";

import NavBar from "components/common/navbar/NavBar";
import TabControl from "components/content/tabControl/TabControl";
import GoodsList from "components/content/goods/GoodsList";
import Scroll from "components/common/scroll/Scroll";

import { getHomeMultidata, getHomeGoods } from "network/home";
import { debounce } from "common/utils";
import { itemListenerMixin, backTopMixin } from "common/mixin";

export default {
  name: "Home",
  components: {
    HomeSwiper,
    RecommendView,
    FeatureView,
    NavBar,
    TabControl,
    GoodsList,
    Scroll,
  },
  mixins: [itemListenerMixin, backTopMixin],
  data() {
    return {
      banners: [],
      recommends: [],
      goods: {
        pop: { page: 0, list: [] },
        new: { page: 0, list: [] },
        sell: { page: 0, list: [] },
      },
      currentType: "pop",
      tabOffsetTop: 0,
      isTabFixed: false,
      saveY: 0,
    };
  },
  computed: {
    showGoods() {
      return this.goods[this.currentType].list;
    },
  },

  methods: {
    _isMobile() {
      let flag = navigator.userAgent.match(
        /(phone|pad|pod|iPhone|iPod|ios|iPad|Android|Mobile|BlackBerry|IEMobile|MQQBrowser|JUC|Fennec|wOSBrowser|BrowserNG|WebOS|Symbian|Windows Phone)/i
      );
      return flag;
    },
    /********* 事件监听********/
    tabClick(index) {
      switch (index) {
        case 0:
          this.currentType = "pop";
          break;
        case 1:
          this.currentType = "new";
          break;
        case 2:
          this.currentType = "sell";
          break;
      }
      // 让tabcontrol保持一致
      this.$refs.tabControl1.currentIndex = index;
      this.$refs.tabControl.currentIndex = index;
      // 点击tabcontrol滚动到相应的位置
      this.$refs.scroll.scrollTo(0, -this.tabOffsetTop);
    },

    refresh() {
      this.scroll.refresh();
    },

    contentScroll(position) {
      // 判断backtop是否显示
      this.topIsShow = -position.y > this.tabOffsetTop - 1;
      // 决定tabcontrol是否吸顶
      this.isTabFixed = -position.y > this.tabOffsetTop;
    },

    loadMore() {
      this.getHomeGoods(this.currentType);
    },

    swiperImageLoadhandle() {
      // 获取tabControl的offsetTop
      // 通过$el属性获取组件中的元素
      this.tabOffsetTop = this.$refs.tabControl.$el.offsetTop;
    },
    // 网络请求
    getHomeMultidata() {
      getHomeMultidata().then((res) => {
        this.banners = res.data.banner.list;
        this.recommends = res.data.recommend.list;
      });
    },

    getHomeGoods(type) {
      const page = this.goods[type].page + 1;
      getHomeGoods(type, page).then((res) => {
        this.goods[type].list.push(...res.data.list);
        this.goods[type].page += 1;
      });
    },
  },

  created() {
    // 1.请求首页的多个数据
    this.getHomeMultidata();
    // 请求商品数据
    this.getHomeGoods("pop");
    this.getHomeGoods("new");
    this.getHomeGoods("sell");
  },

  mounted() {
    if (this._isMobile()) {
      this.$toast.show("如果数据不显示，请尝试刷新或者稍后再试。", 1500);
      setTimeout(() => {
        this.$toast.show("我的GitHub：ConstOwn", 2500);
      }, 1500);
    } else {
      this.$toast.show("建议使用手机浏览器获得更好体验", 9000);
    }
  },
  activated() {
    //  console.log( this.$refs.scroll);
    // 返回页面时滚动到离开时记录的位置并刷新
    this.$refs.scroll.scrollTo(0, this.saveY, 0);
    this.$refs.scroll.refresh();
  },

  deactivated() {
    // 离开页面时记录页面离开时的滚动位置
    this.saveY = this.$refs.scroll.getCurrentY();
    // 离开页面时取消全局事件的监听
    this.$bus.$off("itemImgLoad", this.itemImgListener);
  },
};
</script>

<style scoped>
#home {
  padding-bottom: 49px;
  height: 100vh;
}

.home-nav {
  background-color: var(--color-tint);
  color: #fff;
}

.content {
  height: calc(100% - 49px);
  overflow: hidden;
  position: absolute;
  top: 44px;
}

.tab-control {
  position: relative;
  z-index: 9;
}
</style>
